<header class="header">
    <div class="fix_nav">
        <div style="max-width:768px;margin:0 auto;background:#000000;position: relative;">
            <a class="nav-left back-icon" href="javascript:history.back();">返回</a>
            <div class="tit" style="font-size:18px;"></div>
        </div>
    </div>
</header>